TubeNet

I bought one of these on Amazon for $30. If you have prime the shipping is free. It's the same company that has them listed on Ebay for $50. Goes from 15/32 through 2 inches. Seems like a good deal if your looking for a set. https://www.amazon.com/Repair-Piece-Mag ... dent+balls" target="_blank" target="_blank

How big of a magnet is typically required to use those steel balls effectively?

Merodach wrote:How big of a magnet is typically required to use those steel balls effectively?

There's not a perfect answer to your question. How effective the magnets & balls are depend on the mass of the ball, the temper of the brass, and how much padding is used on the face of the magnet. The larger the ball... the more force a given magnet will exert.

I typically do not use any padding on the face of the magnet... only a greased piece of Mylar from an old drum head,

I use two 1 5/8" diameter x 1 1/4" magnets stacked together and it will get most jobs done but you'll find that balls under around 1" diameter are pretty useless. For smaller diameters like 3/4" or so I like to use barrel dent balls because they have more mass that 3/4" spheres.

Used them on some tuning slides today. Worked pretty well.

Thanks for the before and after shots. Looks much improved. I ordered the same magnets. Can't wait to try them out. (Lord knows my horns need some dent removal) Good luck with the miraphone euphonium. That was an interesting looking little horn.

58mark wrote: very pleased with the results.

Does look pretty good. What kind of padding or whatever did you use, between the ball and the inside surface?